Wireless communication systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code-division multiple access (CDMA) systems, time-division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, orthogonal frequency-division multiple access (OFDMA) systems, and non-orthogonal multiple access (NOMA) systems. Additionally, some systems may operate using time-division duplex (TDD), in which a single carrier is used for both uplink and downlink communications, and some systems may operate using frequency-division duplex (FDD), in which separate carrier frequencies are used for uplink and downlink communications.
By way of example, a wireless multiple-access communication system may include a number of base stations, each simultaneously supporting communication for multiple communication devices, otherwise known as user equipments (UEs). A base station may communicate with UEs on downlink channels (e.g., for transmissions from a base station to a UE) and uplink channels (e.g., for transmissions from a UE to a base station).
As wireless communications systems become more congested, operators are seeking ways to increase capacity. Various approaches include the use of small cells, multiple-input multiple-output (MIMO) techniques, the use of an unlicensed radio frequency spectrum band, and/or the use of wireless local area networks (WLANs) to offload some of the traffic and/or signaling of a wireless communication system. Another approach includes the transmission of non-orthogonal downlink signals to increase the capacity of a wireless communication system. Many of the approaches for enhancing capacity may cause interference with concurrent communications in a cell. In order to provide enhanced data rates through a wireless communication system, it may be beneficial to estimate and mitigate such interference.